Despite socializing a lot when I was working at the office, I pretty much immediately loved working from home after the initial 3 months. I'd gone back in temporarily a couple of times for a few reasons, and the whole environment was... Bad.

I run really hot in general, so being able to control my AC was great, since I swear the office was on 74 with about a thousand bodies worth of heat in a comparatively small space. To emphasize: I tend to open a window when it's anywhere between 0-50F (-17 to 10C) outside.

Everyone had on different kinds of perfume, which just blended into this awful smell on top of whatever cleaning chemicals they used. Having 30+ people talking within earshot made it hard to focus on anything. I could go on. I didn't realize how much I hated it until I started working from home, and it was so much better.